I just discovered another advantage to the blog, one that I never in a thousand years would ever have conceived. Yesterday, I went for a walk at dawn. On the return journey, I stopped to photograph some burdock heads waving in the wind (see above). Look closely at the end of the burrs. You can see the tiny fish hook shape that permits the burr to attach itself to your clothing. The inventor of Velcro developed the product idea from an identical observation.

My discovery was entirely different.

Earlier this year I was plagued by a problem when on walks. I would have this sensation in my left foot near the heel, and in the area outside of the arch. What I felt was a sharp pinprick as if there was something inside the shoe piercing my skin through the sock. Or something sharp embedded in the sock fabric itself.

The sensation was felt with each footfall. It was painful and irritating. I would shift my weight from the left foot and hobble over to a nearby rock or log, sit down, remove the shoe, and check it for foreign objects. None were found. Then I would remove the sock, turn it inside out, and check the sock for foreign objects. None were found.

When I replaced the shoe and sock and continued on with the walk, the sensation returned. On several occasions I stopped a second time and repeated the search process. Nothing was found. I made sure to start each walk with socks straight from the sock drawer. Same problem. With new socks. Same problem. With new shoes. Same problem.

It was my belief that a burdock barb had wormed its way into the shoe, become embedded in the sock, and it was this barb that caused the pinprick irritation. Nothing else made any sense. After a period of dealing with the problem, I learned to “walk through” the discomfort. The irritation would arise, I would feel the pinprick of pain, I would discount it, seek to ignore it, and twenty minutes later I would realize that it was gone.

When I studied the image shown in the header above, I recognized a problem with my prior conception of events. The pinprick pain was experienced in late spring, early summer. I do not have exact dates as I failed to make notes of such a trivial event. I do know I have not experienced the problem during the past several months. And this morning the light bulb went on.

In spring and early summer the burdock thistle is immature and soft. There are no spiny barbs. The thistle head is fleshy. The burdock thistle only matures in the fall. It is then that it dries, and develops the stiff barb structure needed to stick to your clothes. I had been feeling burdock thistle pinpricks when the burdock thistle was not capable of giving pinpricks. During the period when the burdock thistle was capable of giving pinpricks, I have had no experience of the pain despite hiking over 300 miles on forest trails during this period. See the problem?

I am now confident that what I experienced in the spring and early summer was a form of neuropathic pain. This is pain that originates in the pain centers of the brain. Neuropathic pain has no true, real world stimulus associated with it. It feels “real” but it is phantom pain. I suspect this is another outcome of my brain injury.

What is most remarkable is that this was a trivial sort of event, one easily dismissed and forgotten. I had in fact totally forgotten about these pinpricks until I studied the image above and realized it was not physically possible for the immature thistle head to have caused the pain. Coupled with the fact I could never identify any physical source of the pain, the fact I changed out both socks and shoes and the irritation persisted through these changes, the fact the pain initiated and then mysteriously self-resolved during the course of the walk, all of these things lead me to the belief that this series of pain events represented an instance of neuropathic pain.

And this was only discovered due to the blog. Thank you again, Dr. H.

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Just arrived at another insight. To the best of my memory, all of these pinprick pain events were associated with the left foot. I have no memory of ever stopping to remove my right shoe and sock. All memories of the pain events, and the foreign object removal events, solely concern the left foot.

This beggars belief. Out of twenty plus pain events, there is no logical reason for a burr, or any other irritant encountered on the trail, to not have entered the right shoe as well as the left. The absence of such a random distribution, and the fact of the left foot being the sole source of the pain, is further evidence of a neuropathic pain event.